Organometallics 1994,13, 1525-1527
1525
Primary and Secondary Vinylarsines: Synthesis, Stability, and Characterization Jean-Claude Guillemin' and Laurent Lassalle Groupe de Physicochimie Structurale, U R A CNRS No. 704, 35042 Rennes, France Received September 23, 1993" Summary: Primary unsaturated arsines, vinylarsine ( l a ) , isopropenylarsine (lb),(2+ E)-prop-1-enylarsine ( I C ) , and secondary divinylarsine (16) are synthesized by reaction of arsenic trichloride with vinyltributylstannane derivatives 2a-c followed by a chemoselective reduction of the corresponding chloroarsines 3a-d. Compounds la-d are characterized from their spectral data and tungsten complex derivative ( l a ) . T h e arsines 1 exhibit a low stability at room temperature even in a solvent (7112 ca. 30 min). Although many studies have been carried out on vinyl alcohols,' ethenethiols,2 vinylamine~,~ and vinylphosphines,4s6 the corresponding primary and secondary vinylarsines have been only postulated as intermediates.6 It is thus of interest to synthesize these species and to define their spectroscopic characteristics and their stability. Moreover, vinylarsines are of synthetic importance in the field of coordination chemistry' and can be considered as potential precursors of the corresponding arsaalkenes.8 We report here the synthesis of ethenylarsine (la), its spectral identification, and the corresponding tungsten complex. Also described is the preparation and characterization of some substituted derivatives lb-d. Experimental Section Caution: Arsines arepotentially highly toxic molecules. All reactionsand handlingshould be carried out in a well-ventilated hood. Abstract published in Aduance ACS Abstracts, March 1, 1994. (1)Saito, S.Chem. Phys. Lett. 1976,42,399. Ripoll, J. L. N o w . J. Chim. 1979,3, 195. Nobes, R. H.; Radom, L.; Allinger, N. L. J. Mol. Struct. 1981,85,185 and references therein. Capon, B.; Siddhanta, A. K. J. Org. Chem. 1984,49,255.Rodler, M.; Bauder, A. J.Am. Chem. SOC. 1984,106,4025. (2)Strausz, 0.P.; Hikida, T.; Gunning, H. E. Can. J. Chem. 1965,43, 717. Plant, C.; Mac Donald, J. N.; Boggs, J. E. J.Mol. Struct. 1985,128, 353 and references therein. (3)Lovas, F. J.; Clark, F. 0.;Thieman, E. J. Chem. Phys. 1975,62, 1925. Ripoll, J.L.; Lebrun, H.; Thuillier, A. Tetrahedron 1980,36,2497. Eades, R. A.; Weil, D. A,; Ellenberger, M. R.; Farneth, W. E.; Dixon, D. A.;Douglass,C. H. J.Am. Chem. SOC.1981,103,5372.Saebo,S.;Radom, L. J. Mol. Struct. 1982,89,227.Albrecht, B.; Allan, M.; Haselbach, E.; Neuhaus, L.; Carrupt, P. A. Helu. Chim.Acta 1984,67,220.Lafon, C.; Gonbeau, D.; Pfister-Guillouzo, G.; Lasne, M. C.; Ripoll, J. L.; Denis, J. M. N o w . J. Chim.1986,10,69. (4)Issleib,K.;Schmidt,H.Z. Anorg. Allg.Chem. 1979,459,131.Lasne, M. C.; Ripoll, J. L.; Thuillier, A. J. Chem. SOC.,Chem. Commun. 1986, 1428. Lasne, M. C.; Ripoll, J. L.; Thuillier, A. J. Chem. SOC.,Perkin Trans. 1 1988,99. (5)Cabioch, J. L.; Denis, J. M. J. Orgunomet. Chem. 1989,377,277. Gaumont, A. C.; Morise, X.; Denis, J. M. J. Org. Chem. 1992,57,4292. (6)Mlrkl, G.; Baier, H.; Heinrich, S. Angew. Chem., Znt. Ed. Engl. 1975,14,710. Tzschach, A,; Heinicke, J. J. Prakt. Chem. 1976,318(5), 855. Mlrkl, G.; Rampal, J. B. Tetrahedron Lett. 1978,1475. Miirkl, G.; Hauptmann, H.; Merz, A. J. Organomet. Chem. 1983,249,335. (7) Thiollet, G.; Mathey, F.; Poilblanc, R. Inorg. Chin. Acta. 1979,32, L67. Sendlinger, S.C.; Haggerty, B. S.; Rheingold, A. L.; Theopold, K. H. Chem. Ber. 1991,124,2453. (8)Rearrangement of vinylamine, ethenol, ethenethiol and vinylphosphine into the corresponding heteroalkene has been largely studied; see refs 1-3 and: Gaumont, A. C.; Guillemin, J. C.; Denis, J. M. Phosphorus, Sulfur, Silicon Relat. Elem. 1993,76,171.
0276-733319412313-1525$04.50/0
Materials. Arsenic chloridewas purchased from Strem; bis(2ethoxyethyl) ether and decahydronaphthalene were purchased from Janssen. All chemicals were used without further purification. Ethenyltributylstannane~~J~ and tributylstannanell were prepared as previously reported. General. lH and 13CNMR spectra were recordedon a Bruker AC-3OOP spectrometer. IR spectra were obtained using a PerkinElmer 1420 spectrometer and HRMS (high resolution mass spectrometry) experiments were performed on a Varian MAT 311 instrument. Special equipment was used for recording the IR spectrum of la-d in the gas phase: a small Pyrex tube ( I = 10 cm, i.d. = 3 cm) equipped with a stopcock and sealed at each extremity with a KBr window was filled with pure ethenylarsine to a pressure of 100 mbar. To record the mass spectrum, ethenylarsine 1 was directly introduced from a cell into the ionization chamber of the spectrometer. Ethenyldichloroarsines 3a-c. General Procedure. In a two-necked round-bottomed flask equipped with anitrogen inlet, were introduced ASC13 (1.8g, 10 mmol), ethenyltributylstannane 2a-c (10.5 mmol), and catalytic amounts of azobis(isobutyronitrile) (AIBN). Thus, the mixture was stirred 3 h at 60 "C. Distillation in vacuo led to pure vinyldichloroarsine 3a-c. Ethenyldichloroarsine (3a).12 Yield: 82%. Bp: 61 %/40 mmHg. 'H NMR (CDCl3): 6 6.08 (d, lH, = 18.8 Hz), 6.15 (d, lH, 3Jm = 11.3 Hz), 7.21 (dd, 1H, 'JHH = 18.8 Hz, 3Jm = 11.3 Hz). 13CNMR (CDCla): 6 130.3 QJCH = 160.4 HZ(t)),146.3(~JcH = 170.2 Hz (d)). (1-Methyletheny1)dichloroarsine(3b). Yield 85%, Bp: 78 OC/40 mmHg. ~ ~ NMR (CDCl3): 6 2.29 (3H, t, 4 J= 1.3 Hz), 5.72 (9, lH, 'JHH= 1.3 Hz), 5.79 (q,lH, ' J m = 1.3 Hz). I3c NMR (CDCl3): 6 18.3 (VCH 129.2 HZ (q)), 125.9 ('JcH = 160.4 Hz (t)),154.4 ( 2 J =~ 7.2 ~ Hz (q)). HRMS for (C3H&sC12)*+: calcd 185.8984; found 185.897. Anal. Calcd for C3H&sC12: C, 19.28; H, 2.70. Found C, 18.89; H, 2.50. (Z + E)-Prop-1-enyldichloroarsine (3c) ( Z / E 3/1). Yield: 86 % . Bp: 81"C/40 mmHg. (2):lH NMR (CDCl3) 6 2.03 (dd, 3H, 3 J = ~ 7.1 Hz, ~ 4Jm= 1.4 Hz), 6.54 (dq, lH, 3Jm= 10.8 ~ 6.87 (dq, 1H, 3 J = ~10.8~Hz, 4Jm= 1.4 Hz); Hz, 3 J = ~7.1 Hz), = 127.2 HZ (q)), 139.9 (~JcH = 13C NMR (CDCl3) 6 18.1 (~JcH 163.7 HZ(d)),142.9 (~JcH = 155.3 HZ(d). (E): 'H NMR (CDCh) 6 1.99 (dd, 3H, 3 J = ~ 6.6 Hz, ~ 'Jm = 1.5 Hz), 6.48 (dq, lH, 3Jm = 19.4 Hz,3 J= 6.6 ~ Hz), ~ 6.92 (dq, 1H, 3 J = ~19.4 Hz, 'JHH = 1.5 Hz); 13C NMR (CDCls) 6 20.7 (VCH = 128.4 HZ (q)), 139.6 (~JcH = 168.6 Hz (d)), 144.2 (VCH = 152.7 Hz (d)). HRMS for (C3H&sC12).+: calcd 185.8984;found 185.898. Anal. Calcd for C3H&sC12: C, 19.28; H, 2.70. Found C. 18.95; H, 2.46. Diethenylchloroarsine (3d).I2 Compound 3d was prepared starting from 1equiv of AsCl3 and 2.1 equiv of ethenyltributylstannane (2a) in the presence of catalytic amounts of AIBN. Heating at 70 "C during 1 2 h followed by distillation led to 3d. Yield 67%. Bp: 105 "C/760mmHg. lH NMR (CDCl3): 6 5.91 (d, 2H, 3 J = ~18.6~ Hz), 6.05 (d, 2H, 3 J ~ =h11.4 Hz), 6.87 (dd, 2H, 3 J =~18.6 ~ Hz,3 J =~11.4 ~ Hz). l3C NMR ~~~
(9)Seyferth, D.;Stone, F. G. A. J. Am. Chem. SOC. 1967,79,515. (10)Seyferth, D.; Vaughan, L. G. J. Orgunomet. Chem. 1963,1,138. (11)Kuivila, H.G. Synthesis 1970,499-509. (12)The compounds 313 and 3d have already been synthesized by two other approaches: (a) Maier, L. M.; Seyferth, D.; Stone, F. G.A.; Rochow, 1957,79,5884-5889.(b) Maier, L.; Rochow, E. E. G. J.Am. Chem. SOC. G.; Fernelius, W. C. J. Inorg. N u l . Chem. 1961,16,213.
0 1994 American Chemical Society
1526 Organometallics, Vol. 13, No.4, 1994 (CDCls): 6 130.0 ('JcH = 159.4 HZ (t)), 141.9 ('JcH= 164.4 HZ (d)). Ethenylarsines 1. General Procedure. The apparatus already described for the reduction of phoephonatm was usedf The flask containing the reducing mixture (30 mmol of B-SnH in 20 mL of decahydronaphthalene) was cooled at -20 "C, fitted on a vacuum line, and degassed. Then, the ethenylchloroarsine 3 (10 mmol in 5 mL of decahydronaphthalene) was slowly added (10 min) at room temperature with a flex-needle through the septum. During and after the addition, ethenylarsine 1and the carried away solvent were condensed into a cold trap (-120 "C). When the reaction was complete (20 min), the cold trap was allowed to warm to -60 "C and the volatile specieswere condensed with a cosolventonto the cold fiiger (77 K).After disconnection from the vacuum line by stopcockB, the apparatus was filled with dry nitrogen; liquid nitrogen was subsequently removed. The product was collected in a Schlenk flask and characterized by spectroscopy. Ethenylarsine (la). Yield 55%. 'H NMR (CDCb, -30 "C): 6 3.00 (ddd, 2H, 3Jm = 4.4 Hz), 5.81 (ddt, lH, 3Jm18.5 Hz, = 1.7 Hz, 4Jm = 1.7 Hz), 5.92 (ddt, lH, SJ= 11.2 Hz, 2Jm = 1.7 Hz, 4Jm = 1.1Hz), 6.59 (ddt, lH, 'Jm= 18.5 Hz, 3J- = 11.2 Hz, SJm = 4.4 Hz). S ' C N M R (CDCb, 160.8 Hz), 131.5 (Md, 'JCH= 157.3 -30 "C): 6 126.2 (dm, ~JCH Hz, 2 & ~ = 'JCH = 7.6 Hz). HRMS for (czH&)'+: calcd 103.9607; found 103.960. MS, m/z (%): 104 (47.4), 103(6.0), 102 (loo),101 (44.2),100 (17.9),76 (24.9), 75 (18.5). IR (gaseous phase, cm-') U-.CH 3060 (m), U ~ 2100 H (E), u c - c 1591 (m). (l-Methyletheny1)arsine (lb). Yield 52%. 'H NMR (CDCl3,-30 "C): 6 2.11 (m, 3 H , 4 J =~1.6 Hz), 3.03 (m, 2H), 5.29 (lH, m, 4Jm = 1.0 Hz, 2Jm= 1.6 Hz), 5.45 (dq, lH, 2Jm= lJm =: 1.6 Hz).S ' C NMR (CDCla, -30 "C): 6 30.8 ('JcH 126.9 HZ (q)), 125.7 ('JcH 153.9 Hz (t)),138.8. HRMS for (C3H7As)*+: calcd 117.9764; found 117.976. MS, m/z (%I: 118 (74.71, 116 (15.5), 101 (33.5), 90 (1001, 89 (24.31, 75 (12.71, 41 (74.8). IR H (m), U ~ 2095 H (8). (gaseous phase, cm-l): U ~ 3055 ( 2 E)-Prop-l-enylarsine (IC). Yield 62% ( Z / E 3/1). (Z): 'H NMR (CDCl3, -30 "C) 6 1.77 (ddt, 3H, 3Jm = 6.5 Hz, 'Jm = ~ J H=H1.2 Hz), 2.77 (m, 2H, 3Jm = 3.9 Hz), 6.15 (dm, lH, ~ J H H=, 10.8 Hz), 6.30 (dqt, lH, ~ J H H , 10.8 Hz, SJm = 6.5 Hz, 3 J ~3.9 ~Hz); I3C NMR (CDCb, -30 "C) 6 17.6 ('JcH = 125.9 HZ(q)), 116.5 ('JcH 163.7 HZ (d)), 139.5 (VCH = 154.8 H (s), Hz (d)); IR (gaseous phase, cm-9 U-CH 3010 (m), U ~ 2090 UM 1615 (w). (E): 'H NMR (CDCls, -30 "C) 6 1.77 (dd, 3H, 3Jm = 6.5 Hz,4Jm = SJm = 1.2 Hz), 2.89 (m, 2H), 6.15 (m, lH), 6.30 (m, 1H); '3C NMR (CDCls, -30 "C) 6 21.8 ('Jm = 126.5 Hz (q)), 116.3 ('JcH = 163.7 HZ (d)), 142.9 ('JcH 155.1 HZ (d)). HRMS (Z E ) for (CsH7As)*+: calcd 117.9764; found 117.976. MS,m/z(%): 118(23.1),116(9.2),101(12.5),90(78.5),89(29.4), 76 (56.2), 75 (19.8), 43 (69.7), 41 (100). Diethenylarsine (ld). Yield 65%. 'H NMR (CDCb, -30 4.1 Hz), 5.73 (ddd, 2H, VHH,, = 18.5 "C): 6 4.00 (m, lH, 3 J = ~ Hz, *Jm= 'JHH = 1.6 Hz), 5.95 (ddd, 2H, 3 J ~ %= 11.3 Hz, 2Jm = 1.6 Hz, lJm 1.0 Hz), 6.63 (ddd, 2H, s J ~ , ,= 18.5 Hz, VHH, = 11.3 Hz, 3Jm 4.1 Hz). "C NMR (CDCls, -30 "C): 6 129.9 ('JcH= 157.6 Hz (t),3 J c = ~ 7.0 HZ (d)), 132.7 ('JcH= 162.8 HZ (d)). HRMS for (C4H,As)*+:calcd 129.9764;found 129.976. MS, m/z (%): 130 (26.0),115(27.8), 102 (loo), 101 (69.6), 100 (13.2), 75 (11.5). IR (gaseous phase, cm-9: U-.CH 3070 (m), U ~ 2095 H (81, W-C 1590 (w). (Etheny1arsine)pentacarbonyltungsten(4). In a Pyrex two-necked round-bottomed flask equipped with a nitrogen inlet and a magnetic stirrer, were introduced tungsten hexacarbonyl (0.46 g, 1.3 mmol) and tetrahydrofuran (100 mL). The mixture wasphotolyzed 3 h throughthePyrexwallwithamediumpressure mercury lamp. To this solution was added a cooled (-30 "C) THF (10-mL) solution of arsine la (1mmol). The mixture was slowly allowed to warm to room temperature and stirred overnight. Concentration in vacuo led to crude (ethenylarsine). pentacarbonyltungsten (4). Attempts to purify it by silica gel chromatographyonly led to decompositionproducts (yield (crude product): 47%). 1H NMR (CDCla, -30 OC): 6 4.34 (d, 2H, 3Jm
+
+
Notes
Scheme 1
lac : R1 = R z = R s = H
2) cold mp (-80°C)
b :RI=Me;R2=R3=H C
(2) : R,= Me;R, = R 2 = H
R.
c (E) : R 2 = Me; R, = R 3 = H
la4
Asci3
+
2a (2eq.)
A 70°C L &,A 12 hours
I
2) Wld OXP (-80°C) H
3d
Id
= 3.2 Hz), 5.96 (dt, lH, Vm,, 18.0 Hz, 4Jm = 1.1 Hz), 6.10 (dm, lH, VHH,= 10.8 Hz), 6.50 (ddt, lH, SJm = 18.0 Hz, 3J10.8 Hz, 3Jm= 3.2 Hz). '*C NMR (CDCh, -30 "C): 6 122.8 ('JcH 168.2 HZ (d)), 134.1 ('JcH= 159.6 HZ (t)),196.0, 198.6.
Results and Discussion The vinylarsenic dichlorides 3a-c are prepared in very good yields (-85 % ) upon heating arsenic trichloride to 60 OC with 1equiv of vinyltributylstannane 2a-csJo in the presence of catalytic amounts of azobis(isobutyronitri1e) (Scheme l).l3 Divinylarsenic chloride (3d) is obtained by a similar approach starting from k c 1 3 and 2 equiv of 2a. Compounds 3a-d12 are purified by distillation under reduced pressure, and the structures are determined by 'H and l3C NMR spectroscopy. When the reduction of chlorovinylarsines 3a-d is performed using lithium aluminum hydride,14a complex mixture containingalkylated arsines and AsH3 is obtained. The reduction is found to be chemoselective using tributylstannane (BusSnH) without solvent or diluted in a high boiling solvent like bis(2-ethoxyethyl) ether or decahydronaphthalene; in these conditions, only arsines l a 4 are formed (Scheme 1).l6 To limit their decomposition, compounds la-d are distilled off in UQCUO from the cooled reaction mixture (-20 "C) during the course of the addition of 3a-d and separated from the carried away solvent by a cold trap (-60 "C) before condensation (77 K). Arsines la-d are obtained in a essentially pure form in ca. 60% yields and characterized by low temperature lH and l3C NMR spectroscopy. The lH NMR data allow an unambiguous structural assignment,since the chemical shifts and coupling constants are typical of vinylarsenic derivatives.16 We give as an example the NMR data of the parent compound la (Chart 1):the chemical shifts of the vinylic protons are observed between 5.8 and 6.6 ppm ( 3 & , ~ = 18.5 Hz and 3 & = ~ 11.2 Hz)and the signals corresponding to the sp2 carbons at bc2 (126.2 ppm) and 6c,: (131.5 ppm). The presence of vinylarsines la-d is confirmed by the observation of the corresponding molecular ion by high resolution mass spectrometry (HRMS). (13)Some similar experiments have been r e p o d for the prepnrntion of chlorodihydroarrurbenzenederivntivee:MBrkl, 0.;Kellerer,H.; Kneidl, F. Angew. Chem. Int. Ed. Engl. 1979,12,931. Reference 12a (14) Tzschnch, A.; Deylig, W. 2.Anorg. Allg. Chem. 1961, B336, 36. (15) Good reeulta are also obtained when AlHCln in tetraglyme or triglyme is used n~reducing agent (see ref 5). (16) Goedken, V. L.; Brough, L. F.; Rees, W.S., Jr. J. Orgonomet. Chem. 1999,449, 125.
Organometallics, Vol. 13, No. 4, 1994 1527
Notes
Chart 1 'JW: 18.5 Hz 'Jm :7.6 Hz
'Ja : 157.3 Hz
'H NMR chemical shifts and coupling constants of l a
"C N M R chemical shifts and coupling constants of la
Compounds 1 are also identified by the infrared absorptions [la: (gas phase, 100mbar) V&-H 2100 cm-l and -v 1591 cm-11. Treatment of la in THF with (tetrahydrofuran)pentacarbonyltungstenleads to complex 4 which is characterized spectroscopically (eq 1). Arsines la-d exhibit a low stability at room temperature even when kept under nitrogen in a solvent (half-life = 30
min). An insoluble brown polymeric material is slowly formed under these conditions. In conclusion, we have developed a mild synthesis of primary and secondary vinylarsines, unknown so far. Extension of this approach to the preparation of other unstabilized arsenic derivatives is currently under progress.
Acknowledgment. This work has been supported by the 'Programme National de PlanBtologie"(INSU-CNRS). SupplementaryMaterialAvailable: Figures of the 1Hand W NMR spectra of the vinylarsines I (15 pages). Ordering information is given on any current masthead page. OM930662F
